1. Field of the Invention
The present invention relates generally to wireless communications, but more specifically to the configuration and operation of multi-mode wireless modems in a plurality of wireless communication systems.
2. Background
Consumer demand for high data rate services has helped fuel the expansion of the wireless communication industry. In effort to keep pace, the global wireless infrastructure has become an intricate patchwork of largely non-interoperative systems. Worse, to meet the demand for more wireless capability, it is expected that the industry will proliferate, not consolidate, the number of wireless telecommunications standards.
Currently a user wishing to gain access to multiple systems will often carry at least two devices, each device supporting a different system. For example, a personal computer capable of supporting a wireless modem for Institute of Electrical and Electronics Engineers (IEEE) 802.11 access must be re-equipped and re-configured with a different modem, say a Global Packet Radio System (GPRS) modem, when the user leaves the 802.11 coverage area and enters a GPRS only coverage area.
Familiar wireless wide-area network (W-WAN, or simply WAN) standards such as GPRS offer reasonable service quality at an affordable price and have relatively wide coverage. Unfortunately, for many high data rate applications, existing WAN technologies are too slow and expensive. On the other hand, wireless local-area network (W-LAN, or simply LAN) standards such as IEEE 802.11 have proven superior for use in very localized data applications. Moreover, LANs are faster, cheaper, and consume less power than their WAN counterparts. For many subscribers, especially corporate subscribers, LAN access is free—yet, for all practical purposes, a mobile subscriber is not afforded continuous LAN coverage throughout the day. That is, LAN coverage available to a subscriber at work does not usually extend to the subscriber's home. Therefore, it would be advantageous to provide a subscriber a way to switch systems in a more seamless fashion as he or she moves from system to system.
The current technique for managing such switching is clumsy and requires heavy subscriber involvement. Typically, as mentioned, the subscriber must “swap” modem devices. Further, a subscriber must also typically initiate dial-up connectivity upon leaving one system and entering a second. In many cases, multiple drivers and different software are needed for configuration and operation of the devices. Therefore, apart from being cumbersome for the subscriber to manage, swapping modems is also impractical.
Thus, the market would benefit from a single modem device systems that preferably conforms with a standard form factor and that comprises the technology required to access a plurality of communication systems. The design of such a “combinational” modem device, however, raises other concerns. For example, regardless of the form factor, space is almost always a concern in the design of wireless modem devices, especially when more than one wireless communication technology is supported. Further, designing, certifying, and manufacturing such a combinational modem device would be an expensive and lengthy task. A further concern is that there are so many different types of wireless communication systems. To cover all the possible combinations, many different combinational modem devices would need to be manufactured. Manufacturing a multitude of combinational modem devices increases manufacturing costs. Such concerns also need to be addressed in the design of a combinational, or multi-mode, modem in order for such a modem to provide convenient, efficient access to a plurality of wireless communication systems at an affordable cost.